The herbal extract of a yellow-flowered mountain plant long used for stress relief was found to increase the lifespan of fruit fly populations by an average of 24 percent, according to researchers.

But it is the specific way that Rhodiola rosea, also known as golden root, managed to accomplish this that attracted the attention of study leaders Mahtab Jafari and Sam Schriner. They found that Rhodiola works in a manner completely unrelated to dietary restriction and affects different molecular pathways.

”This is significant,” said Jafari, associate professor of pharmaceutical sciences, „because dietary restriction is considered the most robust method of improving lifespan in laboratory animals, and scientists have been scrambling to identify compounds that can mimic its effects.”

”We found that Rhodiola actually increases lifespan on top of that of dietary restriction,” Jafari said. ”It demonstrates that Rhodiola can act even in individuals who are already long-lived and healthy. This is quite unlike resveratrol, which appears to only act in overfed or unhealthy individuals.”

The researchers proved this by putting flies on a calorie-restricted diet. It has been shown that flies live longer when the amount of yeast they consume is decreased. Jafari and Schriner expected that if Rhodiola functioned in the same manner as dietary restriction, it would not work in these flies. But it did. They also tested Rhodiola in flies in which the molecular pathways of dietary restriction had been genetically inactivated. It still worked.

Not only did Rhodiola improve lifespan an average of 24 percent in both sexes and multiple strains of flies, but it also delayed the loss of physical performance in flies as they aged and even extended the lives of old flies. Jafari’s group previously had shown that the extract decreased the natural production of reactive oxygen species molecules in the fly mitochondria and protected both flies and cultured human cells against oxidative stress.